What'd I do wrong?!?

[WLDOR]

So I was messing with my XK Detect X380 in the backyard for only it's second flight… LiPo was fully charged (11.1V 5400mAh), batteries in the Tx were new Duracells… All was going well until the end (obviously?!?).

The quadcopter seemed to either lose all power, or signal, or both, and came crashing down to the ground (fortunately in the ONE small area of soft mud that isnt currently frozen in our yard!). Unfortunately, both motor shafts on the Gimbal broke.

Couple of questions:
1) Anyone have any idea whether this was due to user error, or possibly something more sinister at work in the equipment (I did notice that the gimbal wasn't exactly level through the flight video?)

2) Can gimbal shafts be replaced? Or is this a more expensive 'whoopsie' than I first thought?

 

[ringolong]

Hate that this happened to you.

I don't think it was a signal issue since the gimbal went limp before the motors lost power. It seems like a power issue.

What was the voltage of each cell after the crash?

 

[Jackson]

How cold was it?

 

[WLDOR]

I'm embarrassed to say that I can't check the individual cell voltage right now - my Turnigy chargers all have Traxxas connectors on them, not XT60, so I have to use the supplied balance charger to charge the battery right now (Note to self: order banana plugs, silicon-covered battery wire & XT60 connectors ASAP!)

In terms of outdoor temp, it was around 3C (+/-36F)… it was cool, but that cold that it could drain a brand new 11.1V 5400mAh battery in less than 3 mins?!?

 

[Jackson]

You don't own a multimeter?

 

[ringolong]

How do you know when the battery is too low to stay in the air?

 

[WLDOR]

You don't own a multimeter?

Never thought of that. I'll check.

 

[WLDOR]

How do you know when the battery is too low to stay in the air?

I'm new to quadcopter - I made rookie mistake #1: believe the mfr's quoted flight duration. I assumed that a quoted time of ~20 mins would still allow me at least 5 mins (even at the reduced temp)

Either way, I now have two broken gimbal motor shafts that I need to remedy… any ideas on that front? Is the OEM gimbal worth fixing, or is there a compatible 3rd party offering that might work?

 

[WLDOR]

Multimeter readings (battery has been left alone since the crash - no charge applied to it):

Cell#1: 3.93
Cell#2: 3.94 (actual reading: 7.87)
Cell#3: 3.93 (actual reading: 11.8)

 

[Jackson]

The volts look fine now, after a rest. They were probably sagging lower when you were flying though.

Is it a 2D gimbal? Does it look like this?

Were you the one who got that used one from HK?

 

[ringolong]

hmmmmm. Those numbers look good.

You need to invest in one of these.

http://www.ebay.com/itm/like/181689577374?ul_noapp=true&chn=ps&lpid=82

 

[WLDOR]

The volts look fine now, after a rest. They were probably sagging lower when you were flying though.

Is it a 2D gimbal? Does it look like this?

Were you the one who got that used one from HK?

Yes & Yes. Unfortunately. (That said, I kicked up a stink over the whole open/returned aspect, and they're supposed to be issuing a ~significant~ store credit back to me)

 

[WLDOR]

hmmmmm. Those numbers look good.

You need to invest in one of these.

http://www.ebay.com/itm/like/181689577374?ul_noapp=true&chn=ps&lpid=82

That looks like cheap insurance? Forgive my ignorance - is this an inline module that resides on the quad providing real-time monitoring, or is it a 'moment-in-time" tester that tests the voltage prior/after battery use?

(us non-racing buggy/truggy bashing guys don't worry ~too much~ about LiPo voltage drops: vehicle runs until vehicle doesn't run any more… it doesn't then plummet to the earth, exploding in shards of 'once was an expensive piece of kit'-like componentry!)

 

[ringolong]

It flies on the craft, and starts beeping when the voltage hits a certain level letting you know that its time to land.

 

[Jackson]

Well you could probably replace your broken gimbal with this one.
http://www.gearbest.com/fpv-system/pp_226000.html

For simple stabilization you only need a power lead.

 

[WLDOR]

Thanks for the suggestion, Jackson - that's the kind of thing, but @ half the price of the quad I just bought (which I fear from more recent research isn't quite as good as my somewhat 'rose-tinted' preliminary research might have lead me to believe), I'd have a tough time justifying that expense to my home's CFO!

If I could just replace the broken shafts for the motors, I'd be in business, but I'm drawing blanks finding either suitable shafts or compatible replacement motors (and the mfr has yet to respond to my requests for this info too).

 

[Jackson]

Thanks for the suggestion, Jackson - that's the kind of thing, but @ half the price of the quad I just bought

If yours is like in the pic I posted, that one is a tad more.
http://www.banggood.com/XK-DETECT-X...e-Parts-2Axis-Brushless-Gimbal-p-1003486.html

Lotsa folks have good luck with these. Scope out some YouTube vids.
Eachine Light-2D Brushless Gimbal

 

[WLDOR]

Will do - thank-you for your time/help.

 

[WLDOR]

Wondering whether this might perhaps be a suitable alternative? I might have to fiddle with the motor connections to the controller (split what appears to be a combined connector out into 2 separate 3-pin molex-type connections, as it is on the existing controller board), but if that's the worst I have to do, this might be a pretty reasonably priced option?

 

[WLDOR]

Well I ~think~ I might have found parts for the OEM XK X380-C gimbal…

The XK gimbal appears (visually at least) to be a VERY similar unit to both the Tarot T-2D V2 gimbal and also the Quanum Q-2D . If so, then Tarot sells all of the spare parts for their gimbal products.

Even though I really only need the motor shafts (and not the whole motor assy), I think I might be better advised to bite the bullet and simply order 1 of each of the following to get this thing back up and working again:

Pitch motor
Roll Motor

Can anybody see any other difference that I might be missing to prevent these being suitable replacements?